category of sets
The category of sets plays a fundamental role in category theory. Due to the Yoneda embedding, many results about general categories can be reduced to the category of sets. It is also usually the first example of a category that one encounters.
Satisfied properties
Assigned properties
- is locally small
- is one-sorted finitary algebraic
- is a Grothendieck topos
- is semi-strongly connected
- has an extremal generator
- has an extremal cogenerator
Deduced properties
- is finitary algebraic
- is well-copowered
- is connected
- has an extremal generating collection
- has a generator
- is locally essentially small
- is cartesian closed
- has exact filtered colimits
- is locally presentable
- has a subobject classifier
- has a cogenerator
- has an extremal cogenerating collection
- is accessible
- is cocomplete
- is locally finitely presentable
- is complete
- is a generalized variety
- is multi-algebraic
- has finite products
- is inhabited
- has filtered colimits
- is finitely complete
- has filtered-colimit-stable monomorphisms
- has cartesian filtered colimits
- has a generating collection
- is mono-regular
- is well-powered
- has a regular subobject classifier
- has a cogenerating collection
- is finitely accessible
- is Cauchy complete
- has sifted colimits
- is ℵ₁-accessible
- has effective congruences
- is locally finitely multi-presentable
- is multi-cocomplete
- has pullback-stable regular epimorphisms
- has connected limits
- has products
- has equalizers
- is multi-complete
- has directed colimits
- has ℵ₁-filtered colimits
- is balanced
- has binary products
- has a terminal object
- has finite powers
- is concretizable
- is an elementary topos
- is total
- has connected colimits
- has coproducts
- is finitely cocomplete
- is cofiltered
- is cototal
- is locally ℵ₁-presentable
- is locally multi-presentable
- has a multi-terminal object
- is infinitary distributive
- has coreflexive equalizers
- is filtered
- is ℵ₁-filtered
- has reflexive coequalizers
- has powers
- has ℵ₂-small products
- has binary powers
- has pullbacks
- has wide pullbacks
- has disjoint finite coproducts
- is locally cartesian closed
- has coequalizers
- has finite coproducts
- has a multi-initial object
- is cosifted
- has sequential colimits
- has cosifted limits
- has copowers
- has ℵ₂-small coproducts
- has wide pushouts
- is locally poly-presentable
- has quotients of congruences
- has disjoint coproducts
- is countably distributive
- is distributive
- is extensive
- is sifted
- has countable products
- has ℵ₂-small powers
- has cofiltered limits
- has kernel pairs
- is a quasitopos
- has an initial object
- has coquotients of cocongruences
- has countable coproducts
- has ℵ₂-small copowers
- has binary coproducts
- has finite copowers
- has pushouts
- has a parametrized natural numbers object
- has a strict initial object
- has coequalizers of kernel pairs
- has cocartesian cofiltered limits
- is infinitary extensive
- is countably extensive
- has sequential limits
- has countable powers
- is coregular
- is ℵ₁-cofiltered
- has directed limits
- has ℵ₁-cofiltered limits
- has countable copowers
- has binary copowers
- has cokernel pairs
- has a natural numbers object
- is regular
- has a conatural numbers object
- has equalizers of cokernel pairs
- has pushout-stable regular monomorphisms
- has effective cocongruences
- is epi-regular
- is Barr-exact
- is co-Malcev
- is a pretopos
- is Barr-coexact
Unsatisfied properties
Assigned properties
Deduced properties*
- is not pointed
- is not core-connected
- is not coaccessible
- is not regular-subobject-trivial
- is not gaunt
- is not direct
- is not infinitary coextensive
- is not inverse
- is not unital
- is not strongly connected
- is not discrete
- does not have zero morphisms
- is not subobject-trivial
- is not right cancellative
- is not Malcev
- is not counital
- is not locally copresentable
- is not ℵ₁-coaccessible
- is not essentially small
- is not locally multi-copresentable
- is not locally poly-copresentable
- is not self-dual
- is not thin
- is not additive
- does not have biproducts
- is not preadditive
- is not essentially discrete
- does not have kernels
- does not satisfy CIP
- is not a groupoid
- is not normal
- is not small
- is not essentially countable
- is not locally ℵ₁-copresentable
- is not co-Grothendieck abelian
- is not finitely coaccessible
- is not a dual generalized variety
- is not retract-trivial
- is not coextensive
- does not have cokernels
- does not satisfy CSP
- is not conormal
- is not a Grothendieck cotopos
- is not abelian
- does not have a strict terminal object
- does not have cofiltered-limit-stable epimorphisms
- is not left cancellative
- is not essentially finite
- is not countable
- is not one-way
- is not core-thin
- is not locally finite
- is not locally finitely copresentable
- is not dually finitary algebraic
- is not locally finitely multi-copresentable
- is not dually multi-algebraic
- is not cocartesian coclosed
- does not have disjoint finite products
- is not countably coextensive
- does not have a regular quotient object classifier
- is not regular-quotient-trivial
- is not an elementary cotopos
- is not a precotopos
- is not Grothendieck abelian
- is not split abelian
- is not finite
- does not have a coparametrized conatural numbers object
- is not dually one-sorted finitary algebraic
- is not locally cocartesian coclosed
- does not have disjoint products
- is not codistributive
- does not have exact cofiltered limits
- is not quotient-trivial
- does not have a quotient object classifier
- is not a quasicotopos
- is not countably codistributive
- is not infinitary codistributive
*This also uses the deduced satisfied properties.
Unknown properties
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Special objects
- terminal object: singleton set
- initial object: empty set
- products: direct products
- coproducts: disjoint union
Special morphisms
- isomorphisms: bijective maps
- monomorphisms: injective maps
- epimorphisms: surjective maps
- regular monomorphisms: same as monomorphisms
- regular epimorphisms: surjective morphisms
Functors
The database stores 24 functors based on the category of sets.
- binary coproduct functor on sets
- binary diagonal functor on the category of sets
- binary product functor on sets
- contravariant power set functor
- countable copower functor on sets
- covariant power set functor
- discrete topology functor
- doubling functor on sets
- empty functor to the category of sets
- forgetful functor for groups
- forgetful functor for rings
- forgetful functor for topological spaces
- forgetful functor for vector spaces
- forgetful functor from finite sets to sets
- free group functor
- identity functor on the category of sets
- indiscrete topology functor
- path components functor
- ring idempotents functor
- sequences functor on sets
- simple-group probing functor
- squaring functor on sets
- trivial functor from the category of sets
- walking morphism representation
Morphisms
The database stores 3 morphisms based on the category of sets.
Symmetric monoidal categories
The database stores 2 symmetric monoidal categories based on the category of sets.